In recent years, the whole contents of the human genome have been clarified and post genome studies have been enthusiastically made for the purposes of executing gene therapy, genetic diagnosis and the like. For example, in DNA analysis, a DNA probe fixed onto a DNA microarray substrate is hybridized with a sample DNA labeled by a fluorescent dye or the like to form a double stranded DNA, thereby detecting the sample DNA. This is a technique in which measurement is made after a nucleic acid labeled by a fluorescent dye is PCR-extended and hybridized on a substrate. In these days, a technique using a primer having more amino groups and a technique in which an amino group is introduced into DNA are used.
A fluorescent dye is widely used for labeling and is required to have high fluorescent intensity, to emit light even in a dry state (solid state), to have water solubility, and the like. As the fluorescent dye, for example, Cy3 or Cy5 is used (for example, Non-patent Document 1).
Non-Patent Document 1: Science 283, 1, January, 1999, 83-87